The FDA has approved the first extended adjuvant therapy for early-stage, HER2-positive breast cancer. To further lower the risk of the cancer coming back, neratinib (Nerlynx, Puma Biotechnology Inc.) is indicated for adults who have previously been treated with a regimen that includes the drug trastuzumab (Herceptin, Genentech).
“HER2-positive breast cancers are aggressive tumors and can spread to other parts of the body, making adjuvant therapy an important part of the treatment plan,” said Richard Pazdur, MD, director of the FDA’s Oncology Center of Excellence and acting director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research. “Now, these patients have an option after initial treatment that may help keep the cancer from coming back.”
According to the National Cancer Institute, approximately 15% of patients with breast cancer have tumors that are HER2-positive.
Nerlynx is a kinase inhibitor that works by blocking several enzymes that promote cell growth. Its safety and efficacy were studied in a randomized trial of 2,840 patients with early-stage, HER2-positive breast cancer who completed treatment with trastuzumab within the previous two years. The study measured the amount of time after the start of the trial that it took for the cancer to come back or for death to occur from any cause (invasive, disease-free survival). After two years, 94.2% of patients treated with Nerlynx had not experienced cancer recurrence or death compared with 91.9% of patients receiving placebo.
Common side effects of Nerlynx include diarrhea, nausea, abdominal pain, fatigue, vomiting, rash, stomatitis, decreased appetite, muscle spasms, dyspepsia, liver damage (AST or ALT enzyme increase), nail disorder, dry skin, abdominal distention, weight loss, and urinary tract infection.
Patients should be given loperamide for the first 56 days of treatment with Nerlynx and as needed thereafter to help manage diarrhea. Additional antidiarrheals, fluids, and electrolytes should also be given as clinically indicated to help manage diarrhea. Patients who experience severe side effects, including diarrhea or hepatoxicity, should stop taking Nerlynx. Women who are pregnant or breastfeeding should not take Nerlynx because it may cause harm to a developing fetus or a newborn baby.
Source: FDA; July 17, 2017.